From a practical perspective, unless you want to pursue a career in 
academia,  you should focus on a language like Java or C++, since these 
are far more marketable than Haskell.


I disagree.

I'm not sure what you're disagreeing with? That Java and C++ are more marketable than Haskell?
That focusing on Java or C++ is a bad idea? I'm not saying ignore Haskell. I'm saying if
you spend x amount of time on Haskell then you should spend 2x or 3x on C++ or Java working with
the language and surrounding modules/APIs.


A very important skill these days is the ability to pick up a new
language quickly.  Being familiar with how very different kinds of
programming language work is going to get you a long way there.

True.